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Investigations were conducted on the life-span of "stress" reticulocytes and the fate of the early denucleated large-sized reticulocytes in circulating blood. Reticulocyte disappearance was examined after reticulocyte introduction into the vein and into the peritoneal cavity of polycythemic and normocythemic animals. The results indicated that these introduced reticulocytes matured to red cells by about 36 hours after injection under both the polycythemic and normocytehmic conditions. The large-sized reticulocytes disappeared by about 4 to 12 hours after introduction. The maturation of reticulocytes was largely arrested when the cells were introduced into the peritoneal cavity.

Cholesterol, cholesteryl esters, triglycerides and fatty acids as major neutral lipids and phospholipids were examined in quantitative analysis. The method consisted of three steps: (1) separation of lipids by one-dimensional thin-layer chromatography on silica gel plates; (2) elution of neutral lipids from scraped silica gel with chloroform-methanol (4:1); and (3) colorimetric determination of individual neutral lipids in eluates and phospholipids in silica gel. The conditions were modified for chromotropic acid reaction for determining triglycerides. Laurell's method for determining fatty acids was also modified to apply to quantitative thin-layer chromatography. The accuracy of the modified methods was well-defined as the absorbance values were on a linear curve. A quantitative study was made of the recovery of triglycerides and fatty acids after chromatography. Combining these modified methods and colorimetry for determination of cholesterol cholesteryl esters and phospholipids, the author established a micromethod for determining the major neutral lipids and phospholipids by thin-layer chromatography. Lipids from HeLa, S-3 cells were analyzed to examine the applicability of this method to tissues. The results indicated that the new method permitted a reliable estimation of the major neutral lipids and phospholipids from small amounts of tissues.

The effect of a specific rabbit antiserum to rat alpha-fetoprotein (AFP) was examined on the growth and the plating efficiency of AFP-producing rat hepatoma cells (AH70Btc Clone 10-5) in cultures. The addition of anti-AFP serum to the culture medium inhibited cell growth moderately and inhibited plating efficiency markedly, although no inhibitory effect of complexes of AFP and antibody to AFP was observed on cell growth. Anti-AFP globulin in the immune serum was demonstrated on the cell surface by fluorescent antibody technique. Several clones producing low levels of AFP were obtained by long-term treatment of the original Clone 10-5 cells with anti-AFP serum. These treated clones showed characteristics that differed from the untreated original clone 10-5 cells: The relative plating efficiency of the treated clones on agar plates containing 5% anti-AFP serum was higher than the original Clone 10-15 cells and the amount of AFP secreted by the treated clones was lower.

The effect of murine sarcoma virus of Moloney strain on central nervous system was examined morphologically in Swiss mice of different age. A single intracranial inoculation of cell-free virus solution resulted in the induction of characteristic intracerebral granulomas in 82.8% of the newborn to 5 day-old group, in 71.4% of the 6 to 10 day-old group, and in 68.0% of the 11 to 20 day-old group. The mean latency periods to tumor recognition were 16.5, 21.1, and 33.5 days, respectively. The granuloma consisted of inflammatory cell infilrations, reactive gliosis, and richly developed blood vessels. The lesions consistently contained numerous characteristic large round cells. In cases of long-survival, the findings included reparative changes, such as extensive gliosis, withdrawal of inflammation, and a decrease in the numbers of large round cells and blood vessels. These lesions were tentatively designated as "large round cell granuloma." The early foci of the granoloma were composed of proliferating glial cells and large round cells at the subependymal regions. Electron microscopically these large round cells had abundant intracytoplasmic fibrils quite similar to gliofibrils. Numerous C-type virus particles were present in the intercellular nad perivascular spaces, and occasionally budded from cell membranes of the large round cells and vascular endothelia. The large round cells were considered to be reactive astrocytes activated by biral infection. It was conclided that MSV-M was not a sarcomogenic but a granulomogenic virus in mice. Control animals showed no pathological changes.

We investigated the antitumor effect of purified natural human tumor necrosis factor-beta (nHuTNF-beta) produced by human acute lymphoblastic leukemia BALL-1 cells stimulated with HVJ on pulmonary metastatic tumors of Lewis lung carcinoma (3LL) transplanted into BDF1 mice. nHuTNF-beta showed antiproliferative effects on metastatic tumors in a dose-dependent manner when administered daily for 10 days by the intravenous route. Histological examination of the tumors treated with nHuTNF-beta revealed that the tumor size and number of metastases were much reduced. Lytic cellular changes, including cytoplasmic vacuolation, loosening of the intercellular junction and both cytoplasmic and nuclear swelling, were found, but tumor necrosis was not. These findings indicate a therapeutic effect of Grade IIa according to the histological criteria of Shimosato and Ohboshi. In addition, synergistic augmentation of the antiproliferative effects of nHuTNF-beta by natural murine interferon-alpha/beta (nMu-IFN-alpha/beta) or recombinant murine interferon-gamma (rMuIFN-gamma) was recognized by median effect plot analysis. The results suggested that nHuTNF-beta may well deserve clinical trial as a new immunotherapeutical agent for human cancer.

The biochemical characteristics of cathepsin B secreted from cultured human liver cancer cells were examined. The enzyme activity of culture medium against a synthetic substrate, N-carbobenzoxy-L-arginyl-L-arginine-4-methyl-coumaryl-7-amide, was dependent on the addition of cysteine, and the optimal pH was found to be 6.0. No activity was observed when the enzyme source was fresh medium not used for culture. These results suggest that the enzyme released from liver cancer cells is the thiol-protease cathepsin B. The molecular weight of the enzyme with 90% of the total activity was 40,000. Two cathepsin B molecules were found in liver tissue from patients with hepatocellular carcinoma (HCC); one was equivalent in size to the secreted enzyme, and a smaller one was the same as normal liver cathepsin B (27,000), which was also obtained from HCC-bearing cirrhotic liver. These results demonstrate that two molecules of cathepsin B are synthesized in liver cancer, and that the larger one is released into the surrounding tissue.

Co-cultivation of thymus and spleen cells of Fisher and Lewis rats with lethally irradiated MT-2 cells harboring human T-cell leukemia virus type I (HTLV-I) resulted in the establishment of lymphoid cell lines, FIRT-1, FIRS-1, LERT-1, and LERS-1, respectively. Cells of these cell lines had rat T-cell characters as demonstrated by the positive reaction to monoclonal antibodies (MAbs) to rat T cell antigens (Thy 1 and pan T). They lacked surface immunoglobulins and strongly expressed rat interleukin-2 receptor antigen (Tac) and Ia antigen. Karyotypic analysis revealed that they had the normal rat karyotype in early cultures, but showed marked aneuploidy after long cultivation. None of them expressed HTLV gag proteins (p19 and p24) or virus particles, but they contained HTLV-I proviral DNA monoclonally and weakly expressed pX gene products (p40x). They were not transplantable into syngeneic newborn rats.

In order to improve the postoperative prognosis of gastric cancer patients we have performed preoperative endoscopic intratumoral administration of various biological response modifiers. In the present study we have investigated the kinetics and the immune response augmenting effect of intratumorally injected PSK, a protein-bound polysaccharide preparation, by immunohistochemical methods using anti-PSK antibody and various other antibodies. PSK-containing cells were located in the tumor tissues and follicular marginal zones of regional lymph nodes. Intratumorally administered PSK appeared to be phagocytized by the histiocytes and to cause them to become antigen-presenting cells. These cells may play a major role in augmenting immune responses in gastric cancer patients.

In order to clarify the origin of JC virus-induced brain tumors in rats, the development of tumors was sequentially analyzed histologically and immunohistochemically. Twenty-two of 30 rats (73%), which were intracerebrally inoculated with JC virus within 24 h of birth (group 1), developed, as a group, 45 brain tumors after 12 to 26 weeks. Seventeen of 27 rats (63%), which were inoculated on the 7th day after birth (group 2), developed 37 brain tumors as a group after a time 12 to 40 weeks. The tumors were found exclusively in the cerebrum. The microtumors, which were defined as tumors less than 2 mm in diameter, were located in the subependymal plate around the ventricular system. The microtumors and most part of the macrotumors consisted of cells of undifferentiated neuroectodermal nature, showing nuclear palisades and Homer-Wright-pseudorosette-like structures. Some tumor cells of macrotumors had an astrocytic nature and were positive for glial fibrillary acidic protein, S-100, Leu 7, and vimentin. In conclusion, the target cells of JC virus in rats may be undifferentiated subependymal cells of the cerebrum. The tumor cells show partial glial differentiation as they grow.

To analyze the possible major T cell recognition site(s) of chironomid antigens, we established human T cell lines and clones (CD3+ 4+ 8-) reactive to soluble extracts of the adult midge of Tokunagayusurika akamusi (TAA) and/or Chironomus yoshimatsui (CYA). All T cell lines and clones proliferated heavily in response to relatively large molecular weight fractions of TAA (MW greater than or equal to 15,000). Nine clones reactive to TAA were classified into 3 groups according to reactivity, indicating the existence of at least 3 distinct T cell recognition sites in TAA. Five T cell clones responded to both TAA and CYA, although the two chironomid antigens were serologically distinct. We conclude that T cell recognition sites of chironomid antigens are different from B cell recognition sites in humans.

The rescue of infectious virus from nonproducer BH RSV(-) cells by chick cellular DNA was attempted in order to investigate the functional state of endogenous and exogenous retroviral genes integrated within the cellular DNA. No infectious virus was rescued by transfection with DNAs of chick helper factor (chf)-negative chick embryo cells (CEC), chf-positive CEC or uninfected CEC producing endogenous Rous associated virus (RAV-0). On the other hand, infectious Rous viruses with the phenotype of RAV-0 and RAV-1 were rescued by transfection with DNAs of CEC which had been infected with RAV-0 and RAV-1. From these results, it seems that exogenous retroviral genes integrated in the cellular DNA are expressed rather easily by transfection while those present endogenously are not.

We performed a cytogenetic study on 140 nonpolymalformed patients with mental retardation of clinically undefined origin, using a high resolution banding technique, to determine how much chromosome abnormalities contribute to the etiology of this condition. A total of 15 patients (10.7%) were found to have autosomal or sex chromosomal abnormalities. Autosomal abnormalities included partial monosomy (5 cases), reciprocal translocation (one case), 13/14 robertsonian translocation (3 cases), unbalanced translocation (one case), inverted duplication of 15q (one case) and mosaic trisomy 21 (one case). Sex chromosomal abnormalities comprised structural rearrangement of the short arm of the X chromosome (one case) and 47, XXY in a pure or mosaic form (two cases). It should be noted that four out of the 5 cases of partial monosomy had subtle interstitial deletions, which might have been unidentified by the conventional G-banding method alone. In one case of the robertsonian translocation 46,XY,t(13;14)/45,XY,t(13;14), a small deletion was thought to have occurred in the cells with a chromosome number of 45. Comparison of clinical features of the 15 chromosomally abnormal patients with those of patients with normal karyotypes did not show any clinical parameter indicative of chromosome imbalance. These results suggest that a subtle chromosomal deletion is specific to mental retardation associated with few malformations. We believe that diagnostic evaluation of mentally retarded patients, even if nonmalformed, should include chromosome analysis using a high resolution banding technique.

A case of ovarian leiomyoma is reported, together with histologic, immunohistologic and electron microscopic findings. A solid firm tumor, measuring 6.5 X 5 X 5 cm, was found in the right ovary of a 65-year-old woman. The tumor had an obvious whorled pattern on the cut-surface. Well-differentiated, long spindle-shaped neoplastic cells revealed positive immunoreactivity for anti-desmin. Ultrastructural observations included numerous microfilaments with dense patches in the cytoplasm, micropinocytotic vesicles beneath plasma membranes and continuous basal laminae around neoplastic cells. These findings were compatible with leiomyoma. The possible histogenesis of ovarian leiomyoma was discussed.

A simple cell-free system for studying a priming factor involved in the repair of bleomycin-damaged DNA was established. The template-primer used for the repair DNA synthesis was prepared by treating the closed circular, superhelical form of pUC19 plasmid DNA with 2.2 microM bleomycin and 20 microM ferrous ions. Single-strand breaks were introduced into pUC19 DNA by the bleomycin treatment, and the DNA was consequently converted largely into the open circular form. A system for repair of this bleomycin-damaged DNA was constructed with a priming factor, DNA polymerase (DNA polymerase beta or Klenow fragment of DNA polymerase I), ATP, T4 DNA ligase and four deoxynucleoside triphosphates. After incubation, the conformation of the DNA was analyzed by agarose gel electrophoresis and electron microscopy. The open circular DNA was largely converted to the closed circular DNA, indicating that the single-strand breaks of DNA were repaired. When the priming factor was omitted, DNA repair did not occur. The present system seemed to be applicable to the study of priming factors involved in the repair of DNA with single-strand breaks caused not only by bleomycin but also by ionizing radiation or active oxygen.

Murine adrenal tumor cells (Y-1 clone) were stimulated by adrenocorticotropic hormone (ACTH) and cyclic adenosine 3',5'-monophosphate (cyclic AMP) to produce steroid hormone (delta 4, 3-keto steroids). The steroids were secreted into the medium immediately after synthesis. The optimum concentrations of ACTH and cyclic AMP for stimulation of steroid production were 10(-2) U/ml and 1.0 mM, respectively. In serum-free medium, ACTH and cyclic AMP stimulated steroidogenesis in Y-1 cells, but the amount of steroid hormone in the culture medium was low. However, a high level of steroid production was maintained with medium containing 10 mg/ml bovine serum albumin (BSA). In culture medium containing a higher concentration of BSA, Y-1 cells did not become spherical as is usually the case when steroid production is stimulated by ACTH or cyclic AMP. The morphological changes did not always correlate with steroid secretion by Y-1 cells.

To study the mechanism of DNA excision repair, a DNA repair system employing permeable mouse sarcoma (SR-C3H/He) cells was established and characterized. SR-C3H/He cells were permeabilized with a 0.0175% Triton X-100 solution. The permeable cells were treated with 1 mM ATP and 0.11 mM bleomycin, and then washed thoroughly to remove ATP and bleomycin. Repair DNA synthesis occurred in the bleomycin-damaged, permeable SR-C3H/He cells when incubated with ATP and four deoxyribonucleoside triphosphates. The repair nature of the DNA synthesis was confirmed by the BrdUMP density shift technique, and by the reduced sensitivity of the newly synthesized DNA to Escherichia coli exonuclease III. The DNA synthesis was optimally enhanced by addition of 0.08 M NaCl. Studies using selective inhibitors of DNA synthesis showed that aphidicolin-sensitive DNA polymerase (DNA polymerase alpha and/or delta) and DNA polymerase beta were involved in the repair process. The present DNA repair system is thought to be useful to study nuclear DNA damage by bleomycin, removal of the damaged ends by an exonuclease, repair DNA synthesis by DNA polymerases and repair patch ligation by DNA ligase(s).

Three types of traditional Chinese herb medicine were used to treat 98 patients with advanced esophageal squamous cell carcinoma prior to surgical treatment. Forty-two patients with the same diagnosis were treated with these herbs plus cyclophosphamide (endoxan). One hundred similar patients received surgical treatment without herbs or endoxan treatment as controls. Histologic examinations of surgical specimens were made on all of these patients. Stromal lymphoid-cell infiltration and cancer tissue degeneration were more prominent in Menispernum dehuricum DC- or Chelidonium majus L-treated patients, and were less clear in patients treated with herbs plus endoxan and the controls. The antitumor action of herbs is thought to be brought about by the activation of an immunological rejection mechanism. Herbs plus endoxan may result in the masking of the immunological response of hosts without obviously damaging cancer tissues.

Suppression of the cellular immune system appears to be a prerequisite for the manifestation of adult T-cell leukemia (ATL). In other words, ATL will develop when impairment of the immune system is caused by the infection of human T-lymphotropic virus type I (HTLV-I). This defect of immune surveillance against virus-infected cells may be a result of the impairment of the function of cytotoxic T-cells (CTLs) specific for the HTLV-I-infected cells. The manifestation of ATL could be predicted by examining the function of CTLs in HTLV-I carriers. A new strategy of prevention and therapy for ATL would include an attempt to restore and fortify the CTL function of the host.

The effect of various factors and substrates on the growth of a human hepatoblastoma cell line, HuH-6, which was inoculated at low density in a serum-free medium was examined. Several supplements were required to enhance cell growth of HuH-6. These included cholera toxin (CT), glucagon (Glu) and selenium (Se). Type IV collagen (C-IV) provided the most conductive environment tested for cell growth. These results suggest that CT, Glu, Se, and C-IV are important stimulators for the continuous growth of HuH-6 in a serum-free medium at low density.